Documents WO-A-2009/030526 and WO-A-2011/001273, in the name of the present Applicant, are known. They concern lids and containers provided with said lids to contain a substance, in which there is a pull-open closing element, which remains integral with the lid once opened (“stay-on tab”). In these known documents, a rivet is provided that connects an opening lever to the closing element: the rivet is disposed inside a line of incision that defines said closing element.
U.S. Pat. No. 4,503,989 is also known, which describes a lid with a pull-open closing element, defined by a line of incision with an open profile, to obtain a “stay-on-tab” configuration, which provides an opening lever connected to the closing element by means of an integral rivet, which is disposed inside the perimeter defined by the line of incision.
U.S. Pat. No. 3,773,210 is also known, which describes a lid with a pull-open closing element, defined by a line of incision with a closed profile, to obtain a completely removable closing element. In this case too, a rivet is provided to connect the opening lever to the closing element, disposed inside the closed profile line of incision.
If the substances contained in the containers in question are to be eaten/drunk by humans or animals, there is a strongly felt need to guarantee that the closing element does not enter inside the container, not even minimally, thus preventing contamination of the substance inside: in other words, it is necessary to produce lids and containers that are hygienic. This is to prevent extraneous contaminating or polluting substances from being ingested, such as dust, dirt, germs, bacteria or other pathogens.
This need is even more strongly felt in places where the containers are kept, even only temporarily, in the open or in unprotected places where the strangest substances can be deposited on the lid. In this case, if for example the container contains a drink or a medicine, and if the closing element carries said substances inside the container, even dangerous conditions may be created for the user.
This need is also strongly felt as indicated when pharmaceutical substances are ingested, where the pathological condition of the person or animal ingesting the substances may not support the presence of the contaminants, pollutants or pathogens.
Systems known in the state of the art can suffer the disadvantage that even a minimum part of the closing element may go toward or face, even temporarily, inside the container when it is opened, thus creating hygiene and health problems.
Additionally, with known systems there is a limit to the use of containers with such lids, since there is no guarantee of hygiene and/or non-contamination. This limit prevents the use of such containers for transport and/or storage of contaminating material, or material that must not be contaminated.
Furthermore, with known systems there are limits to the type of content, and they are therefore unsuitable, in certain cases, for the passage of a sufficient quantity of air in a limited time, creating turbulence for the liquid coming out.
There is therefore a need to perfect a lid for containers of substances and a container of substances comprising said lid, which can overcome at least one of the disadvantages of the state of the art.
In particular, the purpose of the present invention, which by way of example can be widely applied in lids of hygienic containers for drinks, is to overcoming the shortcomings of known solutions, and in particular to improve and perfect the inventive ideas expressed in WO-A-2009/030526 and WO-A-2011/001273, obtaining new advantages not seen before.
In particular, the present invention proposes to obtain a closing system which, during opening, substantially guarantees the hygiene and non-contamination of the substance contained in the container, preventing even a minimum part of the closing element from going inside the container during opening.
Indeed it must be remembered that due to the normal construction of the closing element and the opening system connected to it, a perfect cleanliness before opening is neither simple nor easy.
In fact it has been seen that, if the edge of the closing element protrudes even by a little from the rivet or mechanical clamping element which rigidly connects the closing element with the opening lever, either due to a possible lack of uniformity of the line of incision, or due to the presence of lines of weakening that can affect the metal sheet of the lid in various directions, or due to problems of tolerances or other reasons, on certain occasions the protruding part bends and enters under the lower plane of the lid, thus causing an unlimited risk of contamination or pollution. The contamination or pollution can also be two-directional, that is, from the outside to the inside but also from the inside to the outside.
Even if part of the closing element enters only a little, this does not guarantee absolute hygiene, nor does it prevent the risk of contamination.
This disadvantage, even if it only occurs occasionally, is one that drastically limits the use of said lid in containers that contain drinks or foods, and also pharmaceutical substances, supplements, chemical products or special products such as seeds, or laboratory products, etc.
Furthermore, it is also a purpose of the present invention to position the closing element irrespectively with respect to the peripheral edge of the lid, since the position of the closing element can depend on the material—fluid, liquid, pasty, granular, powder or other—present in the container, and also dependent on the instruments used to remove and/or work it.
It is also a purpose of the present invention, thanks to the different structure conferred on the molds and on the production cycle that can be achieved with them, to obtain a very high production regimen of the lids, with a value that can exceed by many percentage points the most evolved production regimens with the same guarantees.
It should be remembered that in characterizing a standard lid as desired, one requirement is not only to obtain depressions and ridges, and the lines of incision, pre-cutting or breakage able to define the closing element, but also to position the lever and attach it to the lid in a precise and defined manner.
The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.